Thank God! The prototype was the actual controller. I wasn't expecting for them to show the PS4, or the price, they probably will hold that until E3, which is the smart thing to do. Now, things that I liked during the conference:

1)Live Streaming with the PS4 without the aid of any PC.
2)The controller.
3)You can play the game while downloading it.
4)Your PSN friends can watch you play a game and they can even take control of your game to help you.
5)Diablo 3 for PS3 & PS4. Blizzard actually porting a game to consoles
6)Although I'm not a fan of Halo, having Bungie do a game for PS4 is pretty big.
7)Watch Dogs.

I didn't get the part of previewing games before buying them. What is the difference from regular demos?
The graphical differences aren't that big of a leap, but still it looks good.

__________________Human Instrumentality ProjectSacrificing older life to create a new lifeform blessed with the fruit of life